To be able to identify a water-pumping windmill, you will need to be able to identify structural components of the mill, as each manufacturer used a different variation on a common theme that can be used to identify different windmill makes. This may seem daunting at first, but once you get your eye in, the differences tend to stand out like a sore thumb. This page is more-or-less an illustrated glossary of windmill components that will help you identify different types of windmill. This page will be a work in progress, and new photos will be added of different variations as I find and photograph them.
The Windwheel
Windwheel of a 10-foot IBC Geared Simplex windmill, Maleny, Queensland.
The windwheel is the technical name for what many people would describe as the propeller, rotor or even "the bit that spins" of the windmill. As it converts the kinetic energy of the wind into circular and ultimately up-and-down motions, the windwheel is under considerable strain and may fail if the wind is too strong or if not maintained properly.
Size is relative; in the case of windmills, the size quoted is for the windwheel, not the entire mill. Hence this 24-foot (7.2 meter diameter) Southern Cross A pattern mill is very large indeed – it is especially imposing because it is mounted on a short tower that give a strong impression of its size! Gilgandra Rural Museum, NSW.
A quick note about windmill size – when a mill is described (e.g. 10 foot Intercolonial Boring Company Geared Simplex), the size refers to the diameter of the windwheel, not the total size of the mill and its tower. Its also important to note that the size is not always precise; for example, the 36 foot Southern Cross E pattern was really 35 foot 6 inches diameter.
Closeup of the windwheel of a 14-foot Southern Cross IZ pattern windmill showing the spoke-like cylindrical steel wheel arms that radiate from the hub; Coonabarabran, NSW, Australia.
The windwheel is comprised of three or more wheel arms, which are spoke-like structures that radiate out from the hub of the windwheel. In the common Z and IZ pattern Southern Cross mills (like this 14-foot IZ pattern at Coonabarabran, NSW), the wheel arms are cylindrical steel bars.
The wheel arms of this 14-foot IBC Geared Simplex are 3mm flat steel bar. Inglewood, Queensland.
Other mills, such as IBC, Comet and Metters, use either flat steel bar or angle iron wheel arms. Angle iron wheel arms are more a feature of larger mills.
Windwheel of a 35-foot Comet B (large C) pattern windmill showing its modular construction, with half of the sails mounted. Toowoomba showgrounds, Queensland.
In most modern mills, the windwheel is modular for ease of construction and divided into identical wheel sections. Each wheel section is mounted between adjacent wheel arms and is comprised of at least two wheel rings (Southern Cross) or wheel rims (Comet & IBC) to which the sails or fans are mounted using sail or fan brackets. Wheel sections are radially repeated to create an entire windwheel. They number of wheel sections (and therefore wheel arms) is diagnostic.
Close-up of the sails of an 8-foot IBC Geared Simplex windmill; Orana windmill hotel, Gilgandra, NSW, Australia.
The windwheel captures the kinetic energy of the wind using the sails or fans (Comet and IBC call them sails, Southern Cross call them fans; they are also commonly called vanes or blades). The number of sails per section, the type of sail, and they way they are mounted, are all important for identifyng different types of mills.
The Aermotor 702 windmill showing the laced sails of the Chicago-type windwheel; Jondaryon Woolshed Museum, Queensland
A very common method of sail mounting is in the Chicago windwheel, which was designed by Thomas O. Perry for LaVerne Noyes, the founder of the Aermotor windmill company based in Chicago, United States of America. In this type of windwheel, the wheel rings are laced through each sail, holding the windwheel together using tension and giving it tremendous strength. Each sail is mounted into a fan bracket, each of which is shaped to the curve of the blade and actually slip onto the blade down its length. They then bolt onto the wheel rims. Many modern windmills use a variation of the Chicago windwheel, including the Southern Cross 1903, Z and IZ patterns, most Metters windmills and, of course, the Aermotor windmills.
The only known example of an 8-foot Intercolonial Boring Company direct-acting open-crank windmill showing the sail mounting brackets that hold the sails forwards of the wheel arms and hoops;
private collection, Queensland
Comet, Metters and IBC use another method of sail mounting that has the sails mounted in front of the wheel arms and wheel hoops on sail mounting brackets. They are shaped in a z-pattern in cross section and bolt onto the blade and the wheel rims.
Closeup of the windwheel of a 12-foot double geared Bryan Colac mill showing how each sail is attached to a sub-wheel arm brace running between the wheel rims. Murrumbateman, NSW.
The windmills made by Bryan Windmills, Colac, and by James Prowse are unique in that the sails are attached to sub-wheel arms. The sails of these mills are also mounted slightly outboard to the inner wheel ring, giving them a curious appearance.
The distinctive windwheel of the Fortescues’ Economy windmill; between Molong and Wellington, NSW
Another unusual windwheel is that of the Fortescue economy mill, which had hollow aerfoil sails mounted on individual wheel arms and a spiderweb-like bracing system. The unusual Ding-Dong windmill also had sails mounted one to a wheel arm, but is a very rare South Australian machine.
20-foot Southern Cross A pattern showing the characteristic double-ringed windwheel; Maclagan, Queensland.
The Southern Cross A, G, H and early model R pattern mills have unique double-ringed windwheels. This means there the wheel rims are duplicated, one on the front and back of the windwheel, giving it a curious, cage-like appearance.
The double-ringed windwheel is very obvious when viewed from the side. This mill is a 10-foot Southern Cross G pattern; private collection; Queensland.
Each fan (what Southern Cross call the sails in all their manuals!) is mounted within the cage-like structure formed by the double-ring by spacers. Southern Cross also called the double ringed windwheel an axial windwheel on their patent documents, but the name never caught on.
This massive 30-foot Southern Cross R pattern Seneschal windmill has a double ringed windwheel; Tharwa, ACT.
Double ringed windwheels were used for some of the largest windmills ever built, including the monstrous 36-foot (actually 35 foot 6 inch) E pattern, of which there were just two made. This was the actual biggest Australian windmill – the so-called biggest windmill at Penong – a 35 foot Comet B pattern – had its sails moved outwards to give it extra size. In my book, that’s called cheating and it does not count! The 30-foot R pattern Seneschal mills were made in larger numbers, and a few can be seen easily, like the one shown above, which is at the Lanyon Homestead at Tharwa, just outside Canberra. Seneschal windmills are icons of the Australian outback due to their size; they make a memorable sight when silhouetted against the glowing red of an outback sunset.
The Southern Cross Seneschal started out as a double-ringed design, but was later modified to have a single ring and an extra third the number of sails. This 25 foot R pattern has a single-ringed windwheel and is in the Toowoomba TAFE windmill collection, Queensland.
Southern Cross later learned that the double rings were unnecessary overkill that actually slowed their mills down for being too heavy – in fact, tests showed that a single set of wheel rims could even support an extra sail per windwheel section, allowing extra torque for less weight. The revised 25 foot single ring Seneschal proved this by pumping the equivalent of the 30 foot mill, despite its smaller size! Had Southern Cross learned this a few decades earlier than they did, the Comet B pattern windmills may not have enjoyed the success they did on inland stock routes, as Seneschal windmills have a heavy-duty oiling system that makes them easier to service.
The amazingly ornate wind buckets of the Mast Foos Iron Turbine, a once common mill now known from a handful of examples worldwide. Many of these are in Australia. Jondaryon Woolshed Museum, Queensland.
A truly unique windwheel is that of the Mast Foos Steel Turbine. Its sails were modified into unusual and unique wind buckets to catch the wind. This type of mill is very rare in Australia,but they can be seen in a few collections.
Another method I used to identify different types of windmills is the windwheel ratio, or the ratio between the length of each sail and the radius of the windwheel. It is an easy way to separate the smaller 6-10 foot Z and IZ pattern Southern Cross mills from the larger 12- and 14-foot windwheel mills, for example.
The hub and wind engine
Southern Cross A pattern windmill showing how the wheel arms are bolted to the hub; Jondaryon Woolshed windmill collection, Queensland.
The hub itself has two (or sometimes more!) discs to which the wheel arms are attached using bolts.
Three disc hub of the 1915 pattern Southern Cross windmill.
The Southern Cross 1915 pattern was the only windmill in the world that had three hubs! This mill is very rare now and it is unlikely any are still standing. This one is in a private collection.
Southern Cross IZ pattern, showing how the wheel arms screw into the hub. Carwoola, NSW.
The Southern Cross IZ pattern is unique in that the wheel arms screw into the hub, instead of being bolted onto discs.
The early version of the 5-foot Alston Aqua has sails that attach directly to the hub. Maclagan Memories Museum, Queensland.
Several Alston mills have their sails attached directly to the windwheel hub, and unusual laced bracing to give tension to the windwheel. Mills with this type of windwheel include the Alston Dot mill and the Alston Aqua. A very rare mill called the Thompson also had this type of windwheel.
Alston 33 planetary windmill; Lake George, NSW.
Another Alston design, the 33 Planetary, has a windwheel with one sail mounted to each wheel arm. This mill is not so common, and appears to have suffered from vibrations (possibly resonance). Its successors had normal windwheels.
The first gearbox iteration of the Z-pattern Southern Cross windmill. This example may look like its beyond repair, but it has since been fully restored and is now back up and running!
The engine of the windmill converts the rotation of the windwheel into a force that can be used for pumping. Rotational energy is transferred to the engine via the hub, which is in turn mounted on the crankshaft. The transfer of the rotation of the windwheel into the up-down pump motion of the crankshaft is achieved in either of two ways. In geared mills, a gearbox is used to reduce the crankshaft rpm relative to the windwheel - that is, several revolutions of the windwheel are needed to give one up-down pump stroke. This is done to give the mill more power.
This close-up shows how the crank of a 35-foot Comet B pattern windmill is attached to the pump-rod, generating up and down pump stroke for each turn of the windwheel. The holes on the disc at the rear of the crank allow the length of the pump-rod stroke to be varied to suit different pumping requirements. Toowoomba Showgrounds, Queensland.
In direct acting mills, the crank is attached directly to the pump-rod, so one revolution of the windwheel equals one up-down pump stroke, making the mill more efficient in having more pump strokes, but less powerful than a geared mill. Direct acting mills are generally much larger than geared mills because the torque created by their sheer size compensates for the loss of power derived from being direct action.
Southern Cross A pattern windmill showing a counterweight attached to the end of a wheel arm. Jondaryon woolshed museum, Queensland.
In direct acting mills, a counterweight is usually mounted directly onto two wheel arms, one on the opposite side of the hub to the crank and another mounted one wheel arm ahead. The counterweights act to offset the unequal load of the upwards pump stroke by pulling the windwheel over the top of the turn.
The counterweight of this AGE pattern Southern Cross is mounted on a supplementary triangle-shaped arm, here pointing at the 8 o’clock position. The Bearded Dragon Hotel, Tambourine, Queensland.
Southern Cross AG-E mills are unique in having a special pair of counterweight arms mounted on the windwheel specifically for carrying this counterweight.
The pulley under the cross-bracing of this IBC New Simplex mill is its counterbalance mechanism. A weight attached to a chain offsets the weight of the water being pulled up, removing uneven force on the windwheel.
The Bearded Dragon Hotel, Tambourine, Queensland.
Instead of windwheel-mounted counterweights, the IBC New Simplex used a pulley counterweight system that put less stress on the mill, as counterweights mounted on the windwheel proper cause them to be inherently unbalanced.
The view inside of an IBC Geared Simplex mill’s gearbox. This somewhat rusty example is awaiting restoration in a private collection. These mills have a very robust cast iron helmet. The nub on the helmet keeps the tail casting from popping out of its housing, the cylinder on the upper left of the gearbox in this view. Private collection, Queensland.
Depending on whether the windmill is geared or direct acting, the engine can be comprised of a gearbox or merely a mount for the bearings on which the crankshaft is mounted.
The engine of this 8-foot direct-acting open-crank mill is exposed to the weather. The crank runs from right to left and is mounted on grease lubricated bearing blocks. This mill is not allowed to run very often because it needs to be greased every few weeks to keep it running silently. Its owner ran it for me – the first time it had turned in many years – and it made a racket! Private collection, Queensland.
The simplest mill engines are open crank, with everything exposed to the weather. These mills are mechanically simple but need a lot of maintenance and are usually covered in grease. Very few are still in use.
The dust cover of this 10-foot C pattern Comet is the galvanised shell between the tail and the hub. This cover is often missing. Bywong, NSW.
Later direct acting mills had dust covers to protect the bearings from contamination. Beware that the Comet C pattern's dust cover is often lost and may give the impression that the head is not enclosed.
17-foot Southern Cross R pattern Seneschal; Millmerran, Queensland.
The direct acting Southern Cross Seneschal mills have a distinctive pipe-like cover (properly called a helmet).
The view under the hood of a Southern Cross R pattern Seneschal mill; private collection, Queensland.
Underneath the helmet is a heavy-duty pumping system, and a complex oiling system that operates like that of a car.
The cast iron oiler of the Southern Cross A pattern was anchor-shaped and very efficient at oiling the mill – but very dangerous to hands that got in the way. Private collection, Queensland.
The R pattern’s predecessor, the A pattern, also had an efficient – but dangerous – oiling system. Under its hinged lid was an anchor-shaped cast iron oiler mounted on the crank. The immense torque generated by these large mills (which had up to 30-foot diameter windwheels) was known to amputate the fingers of the unwary. These mills still operate in some numbers on Queensland’s Darling Downs.
Alston 8-foot Double Crank windmill showing its open-geared engine; Jondaryon Woolshed Museum, Queensland.
Open geared engines are characteristic of the earliest geared windmills. They needed a lot of attention to keep them lubricated and the gears free of contaminants. They were also messy, throwing grease everywhere.
This derelict 8-foot Danks’ Billabong is now used as an advertising platform just north of Warwick on the New England Highway, Queensland.
Not many open geared mills are still in operation; most are now derelict or scrapped, but a few are now used in very different roles, including for advertising and as garden ornaments.
The Southern Cross IZ pattern mills have an angular galvanised steel helmet that sits above the gearbox and protects the engine. Wiseman’s Ferry, NSW.
Modern mill engines are enclosed with a helmet that keeps dirt and rain off the gears.
The helmet of this 10-foot Southern Cross H pattern is distinctive by being tall and narrow, making it a useful feature for identification. Toowoomba TAFE windmill collection, QLD.
The shape of the helmet can be diagnostic too. For example, compare the angular helmet of the IZ pattern shown above with the cylindrical helmets of the Southern Cross H, AG-E and R pattern windmills.
A dilapidated Fortescues’ Economy mill showing its distinctive letterbox-like helmet; Wallendbeen, NSW.
The Fortescues’ Economy mill also has a distinctive helmet that looks like a letter box! It was one of the first welded mills anywhere in the world (most mills have cast iron gearboxes or heads).
Engine of an Alston Gearless 10-foot windmill at the top of its stroke, showing the oval yoke and roller bearing that replaces gears; Toowoomba TAFE windmill collection, Toowoomba, Queensland.
Alston was an innovative windmill company based in Melbourne, Victoria, that produced some very unusual – but effective – windmill engines. One, called the Planetary, has a remarkable gearing system where the gears ran on a circular pinion inside the gearbox. Another invention, the Alston Gearless windmill, was an amazing machine that is neither direct acting or geared. Its crank has an arm that moves a roller bearing through a full circle, that in turn drives an oval yoke (sometimes called a scotch yoke) up and down, with the bearing sliding back and forth across the yoke as it is rotated on the arm through 360-degrees. They are now rather rare, but I have seen photos of a few still standing (and even some still in use!).
Here is a video of the gearless mechanism in action (my father is turning the crank):
The tail
The unmistakeable corrugated iron tail of an Australian icon – the Southern Cross Z pattern (14 foot); Upper Yarraman, Queensland
The tail of a windmill is used to steer the windwheel into (or out of) the wind. They are often key to a successful identification because, unless they are painted over or severely aged, they usually carry the name of the windmill's maker. However, even if the name of the mill's maker is obscured, the shape and form of the tail is also diagnostic at a glance. For general anatomy, the pipe or frame on which the tail is mounted is called the tail bone. The tail vane(s) is/are the sheet of steel that provides the tail with enough surface area to turn into the wind. Many Australian windmills have corrugated sheet iron tails, like the classic Southern Cross Z mill shown above.
A 10-foot Southern Cross mill unfurled and pointed into the wind. The heavy double-ringed windwheel needs a strong gust to start it turning, but will keep turning in relatively light breezes once started.
Private collection, Queensland.
The tails themselves are mounted on a hinge that allows the tail to be pulled out of the wind. This is done manually using pullout chains, or automatically by a neat gravity trick.
This 10-foot IBC Geared Simplex shows how the tail vane hinge is offset from the windwheel shaft. There is a reason for this. Colinton, Queensland.
In most windmills, the tail is offset to one side of the windwheel. This means that when the wind pushes on the windwheel, it will want to fold in towards the tail. The stronger the wind blows, the stronger the force acting to turn the windwheel out of the wind become
Alston 10-foot Enclosed Double Geared (EDG) windmill showing the distinctive art-deco tail cut-outs that are characteristic of most Alston mills. Note also the strong angle at which the tail of this mill needs to rise to enter the furled position. Helm Wines, Murrumbateman, NSW.
To stop the windwheel being pushed out of the wind at low wind speed, the tail is hinged at an angle so that it will be pushed upwards as it turns on the hinge. This requires extra force to push it upwards. The size and weight of the tail, and the angle the tail rises, are carefully combined to make sure the windwheel will fold in automatically at a certain critical wind speed to avoid the mill being wrecked. When the wind speed drops, gravity pulls the tail back down and around, and the mill once again turns into the wind. This process is gradual in gusting winds, but can be abrupt in a sudden wind gust.
A dilapidated Webb windmill showing the distinctive art-deco style cutouts on the tail. Maclagan, Queensland.
The shape of the tail is very diagnostic for identifying mills. For example, Alston and Webb mills are immediately obvious because of their unique art-deco style cut outs.
The distinctive trapezoidal tail of the Comet C pattern mill; Jerrabomberra, NSW.
Others, like this Comet C pattern, have trapezoidal, flat sheet steel tails.
Windmills made by Danks have distinctinve triangular tail vanes, like this one at Canowindra, NSW.
Fortescues’ IXL windmills have a small, supplementary vane that helps steer the windwheel out of stronger winds. It was normally a feature of American mills. Wiseman’s Ferry, NSW.
A rarity in Australia is the storm vane. This type of vane is smaller than the tail vane proper, and is held in a fixed position behind the windwheel. When the wind hits a certain speed, the storm vane turns the windwheel of of the wind automatically. This is a feature of the IXL mill made by Fortescues’, but may also mean you are looking at a rarer American import.
Double sheet tail of a 21-foot Southern Cross R pattern or Seneschal windmill; D’Aguilar Highway at Villeneuve, east of Kilcoy, Queensland.
Many larger windmills have a double tail made of separate sheets of corrugated iron, one mounted above and one mounted below the tail bone. The larger sized Southern Cross R pattern mills, all Comet D-pattern mills, the IBC Simplex and New Simplex mills all have double tails.
The classic Australian icon – a Southern Cross IZ pattern windmill at sunset flying the Southern Cross marque proudly on its tail. Jerrabomberra, NSW, Australia.
The marque of the manufacturer painted on the is a very obvious identifying feature. Some, like Southern Cross, are a cultural icon (at least in Australia).
The 1903 pattern mill made by the Toowoomba Foundry gave the Southern Cross company – and their iconic Australian windmills – their names. Toowoomba TAFE windmill collection, Queensland.
A little known fact is how the Southern Cross windmills got their name. It all started with the 1903 pattern mill, which was an open geared design built in response to competition from overseas companies in the early 1900s.
The pattern of bolts on the tail reminded G.A. Griffiths, a member of the family who ran the (then) Toowoomba foundry at the time, of the Southern Cross constellation – and used it to market this otherwise innocuously named mill. The name stuck and came to be associated with the Toowoomba Foundry’s mills and other products to the point where the name of the business was changed. And so an icon was born!
Wait, what? Same mill, two names? What gives? Alston double crank windmill; Jondaryon woolshed museum, Queensland.
Its important to note that the name on the tail may not necessarily be the name of the manufacturer. Alston windmills were sold in Queensland and New South Wales by Buzacott’s, a rural supply firm, who rebranded the mill on one side of the tail as free advertising. The Webb mill shown above also has another name on its tail, but it is too washed out to be legible.
Note everyone plays fair with windmill names – this 8-foot IBC Geared Simplex has been completely rebranded by Moffat-Virtue, who completely rebranded IBC mills as their own. Note that the tail sheet has been installed upside down on the tail pipe; the image at right has been digitally flipped so the marque can be read clearly. Orana windmill hotel, Gilgandra, NSW.
I have also seen Intercolonial Boring Company Geared Simplex mills rebranded by the Sydney rural supply firm Moffat-Virtue (noting they also used to crudely airbrush out the IBC marques on mills shown in their catalogues!), and have also been told of the same type of mill being sold under the name Apollo 8.
Southern Cross 10 foot Z pattern mill; Wiseman’s Ferry, NSW.
Some farmers also put the name of their farm on the tail, like the mill above.
The tail of this six-foot Comet C pattern mill has a Lysaght galvanising proof marking in addition to the Comet marque. Sutton, NSW, Australia.
There may be additional markings on the tail that provide a glimpse into when the mill was made. For example, the 6-foot Comet C pattern shown above has markings that read "Lysaght Queen's Head Australia", with Lysaght being the name of a company that manufactured galvanised steel sheets and later became Bluescope Steel. This particular stamp shows that the steel for the tail was galvanised well after World War Two, as rationing of steel for the war effort resulted in galvanising to a different standard that was denoted by a different type of Lysaght's stamp.
A rather peppered Alston 1927 pattern windmill; Lake George, NSW.
Speaking of markings on windmill tails, it seems some folks think that windmill tails are there to be used for target practice – it is not uncommon to see derelict mills with more bullet holes than tail. In fact, it can be hard to find windmills without bullet holes in some areas.
Danks’ Busy-B was a post-mounted mill used for domestic pumping that is now very rare and hard to find. For windmill enthusiasts, there is nothing worse than finding a gem like this that has been peppered by someone without anything better to do with their time than shoot up a windmill. Tarago, NSW.
Shooting damage can make it very hard to restore windmills, especially for museums that focus on keeping a piece of history as intact as possible. As windmills are disappearing at a great rate due to the current craze for solar pumps, there is a concerted push to find and preserve old mills, so shooters take note – think twice before shooting up that windmill. If you wouldn't shoot an antique car, then why shoot a windmill that has similar heritage value?
The tower
This unorthodox looking mill is a hodge-podge of an Alston four-post tower, a 14-foot Southern Cross windwheel on a gearbox that looks like it came from a much smaller mill, and a home-made tail.
Mills like these can be confusing to identify, even for experienced windmillers. They are testament to enterprising farmers, but can be very dangerous – this one is also mounted on timber footings that could rot and cause the mill to collapse. The guy wires are further proof that this design is not self supporting! This one stands – precariously – at Malling, QLD.
Towers can be extremely useful for identification, but can also be a trap for the unwary. This is because the head of one windmill make can be attached to the tower of another make of mill that had been damaged or failed. A common combination is the head of a Southern Cross Z or IZ pattern attached to a old Alston or Comet tower. Southern Cross in particular offered stub towers with different numbers of legs to suit different towers to exploit this market. I use the term native tower to refer to the tower that was provided for a specific mill as standard (noting that Southern Cross offered four-post towers at an extra price).
Another unorthodox looking mill, this is an IBC Geared Simplex that has been mounted onto a well tower of an Alston mill that had presumably failed. This mill is liable to fail too,
because the pull-out chain on the tail has broken, it was squeaking from no oil and the broken pump rod means it has no load – a classic setup for windmill failure. Boonah, Queensland.
But sometimes you can get very weird combinations, such as a three-post Southern Cross Z or IZ pattern mounted on a four-post IBC mill tower. The IBC Geared Simplex above has been mounted on an Alston tower – its legs are flared because this tower was designed for being installed over open wells. This type of tower is also called the Alston well tower.
This dilapidated Alston Aqua was a 5-foot mill designed to be mounted on a timber post; Maclagan Memories Museum, Queensland.
Some early mills could also be mounted on a simple post, such as the Alston Aqua and Dot mills. Post mounted mills were small (five or six foot windwheel) designed for light domestic pumping, such as transferring water from a tank collecting rainwater from a homestead roof, to a tank mounted on posts to provide gravity fed water pressure.
Count the legs (of the windmills, not the cows!). The 8-foot Southern Cross Z pattern at left has three, while the 8-foot Geared Simplex at right has four. Malling, Queensland.
The most obvious difference between many towers is the number of legs. The native towers of most Southern Cross mills have three legs, while Alston, Comet and IBC have four legs.
IBC towers are unique because they narrow and become vertical at their apex. This was from a 14-foot IBC Geared Simplex; Private collection, Queensland.
Another obvious difference between different makes is whether the tower angles evenly across its length, or narrows abruptly at a specific point. Alston and IBC towers, for example, narrow abruptly from a relatively broad base. In contrast, Southern Cross and Comet towers follow the same angle evenly along their entire length.
The problem with the tower of Southern Cross Z and IZ pattern mills – like this six footer – is that you run out of tower to hang onto while standing on the platform!
Twenty feet also seems a lot higher up when you are actually standing on the rickety boards! Four Winds Winery, Murrumbateman, NSW.
The tower platform is also diagnostic. IBC Simplex mills have a very substantial square platform made of hardwood timber, whereas IZ and Z pattern Southern Cross mills have a very narrow platform made of hardwood (earlier mills) or a narrow strip of steel.
Bryan Colac mills, like this 12-foot double geared mill, have a unique platform, with a pad either side of the tower. Murrumbateman, NSW.
Bryan of Colac and Varcoe mills also have a unique platform that is divided in two, with one platform mounted each side of the tower.
The pitman arm of this 8-foot IBC direct acting open crank Simplex is mounted under the right side of the platform. Private collection, Queensland.
Direct acting IBC Simplex mills can be told apart at once because they have a pitman arm mounted under the platform. The pitman converts the circular motion of the windwheel and crank into pure up-and-down vertical motion to avoid stressing the pump rods and damaging the pump.
Southern Cross A pattern windmill showing the rotating and fixed platforms; Jondaryon woolshed museum, Queensland.
Many Southern Cross mills also have a rotating platform that is attached to the head of the mill. It rotates with the head to face the wind, allowing maintenance to be carried out easily.For example, Southern Cross Z- and IZ-mills with a windwheel diameter larger than 10 foot always have a rotating ladder attached to the head, while the smaller 6- and 8-foot mills of that make do not.
You need to look closely to see the ladders on Alston mills – they are angle iron lengths bolted to one of the tower legs (here the one at far left). This is a 10-foot Aston Enclosed Double Gear (EDG) mill;
Helm Wines, Murrumbateman, NSW.
The type of ladder affixed to the tower is also important. Alston, Aermotor and Metters towers can be told at once because they have the ladder integrated into one of the legs, with spurs or even U-shaped bracing welded to the leg. For most other mills, the ladder is bolted to the side of the tower.
The rotating ladder attached to the heads of Southern Cross Z and IZ pattern mills gives a clue to their size – unless someone has made a Frankenstein like the mill shown at the top of this section!
The tower on this Z pattern mill is a sure sign it is a 10-footer – as it has the same number of sails and wheel arms as the 8-foot, it is hard to tell its size otherwise. Upper Yarraman, Queensland.
Many larger mills also had a second, rotating ladder attached to the head of the windmill. For example, Southern Cross Z- and IZ-mills with a windwheel diameter larger than 10 foot always have a rotating ladder attached to the head, while the smaller 6- and 8-foot mills of that make do not.
The rotating ladder of this 16-foot Comet D pattern is economical and functional, but requires some gymnastics to get on to. The steel loop is at the top of the ladder is a fall guard. Wiseman’s Ferry, NSW.
The platform can be a bit of a leap to get onto, like on the Comet D pattern mills. The upper tower of the D pattern has angle iron girts that point outwards, which serve as a ad-hoc ladder. I have it on good authority that it is not a nice feeling to be standing on this platform and have the mill turn suddenly into a gust of wind that comes from out of nowhere!
The maze-like view up the tower of an 8-foot Southern Cross IZ pattern mill. Note the wire cross bracing, which was replaced by flat steel bar in later examples of this type of mill. Jerrabomberra, NSW.
The tower legs are typically built from steel angle overlapped and bolted together. Girts, also made of angle iron, provide the framework that holds the tower together.
The narrow upper tower and tight cross bracing of the IBC Geared Simplex mills could make it difficult to remove long lengths of pump rod from down a bore. This is a 10-foot mill at Diamond Valley, Queensland.
Cross bracing uses tension to give the tower its strength. It may be made of a thick wire (eg. Southern Cross Z pattern mills and early model IZ patterns), or flat steel bar. Sometimes, cross bracing can be a burden – the tight cross bracing of the upper tower on IBC Geared Simplex mills could make it difficult to remove the pump rod – especially when a 14-foot mill had been mounted over a deep bore on a smaller tower than it should have had!
Acknowledgements
I am grateful to Gary and Peta Lovell (Southbrook, QLD), Peter and Patricia Wearne (Warwick, QLD) and Robert and Di Mackenzie (Wiseman’s Ferry, NSW) for allowing access to their windmill collections and, along with Tom Glastonbury and Dudley Horn, for very helpful discussions.
References
Southern Cross (no year given). Instruction manual for Southern Cross direct acting windmills "R" pattern (Marks RF, RG, RH and RK). Toowoomba Foundry: Toowoomba
Southern Cross (no year given). Instruction manual for Southern Cross 'IZ' pattern windmills (IZ-A, IZ-B, IZ-C, IZ-D, IZ-E). Toowoomba Foundry: Toowoomba.
Southern Cross windmill and engine company limited (1941). The Southern Cross 1941 Catalogue. Toowoomba Foundry: Toowoomba.
Southern Cross windmill and engine company limited (1946). The Southern Cross 1946 Catalogue. Toowoomba Foundry: Toowoomba.
Toowoomba Foundry (1972). Southern Cross Machinery 1972. Toowoomba Foundry: Toowoomba.
Sydney Williams & Co. (Pty.) Ltd. (no year given). Erecting instructions 6 ft. to 14 ft. "C" pattern "Comet" mills. Sydney Williams & Co.: Rockhampton.
Sydney Williams & Co. (Pty.) Ltd. (no year given). Erecting instructions towers for 6 ft. to 14 ft. "C" pattern "Comet" mills. Sydney Williams & Co.: Rockhampton.
Intercolonial Boring Company Ltd. (no year given). Instructions for erecting and operating IBC "Simplex" geared self-oiling windmills. Intercolonial Boring Company: Brisbane (pp. 1-20)
Intercolonial Boring Company Ltd. (1952). Catalogue No. 6. Intercolonial Boring Company: Brisbane.
